Node fixation in self-twist yarn
AssigneeWWG Industries, Inc.
InventorsAlan H. Norris, Phillip W. Chambley
Life of this patent
Estimating the term…
Abstract
False-twisted yarns are continuously fed to a locking mechanism on a rotating guide wheel. The locking device has a clamping shoe for engaging the yarn, after which the direction of false twist is reversed. Two additional clamping shoes then engage the yarn upstream and downstream of the first clamping point. The first shoe is then retracted to permit the twist between the additional shoes to cancel, and a fluid vortex is used to entangle the yarn filaments, locking the node.
Claims7
A method of joining yarn strands at longitudinally spaced points in a continuous yarn production system of the type having means for forming and longitudinally moving a plurality of yarn strands, and reversible twisting means for imparting false twist to each of the longitudinally moving strands in alternating length segments of S and Z twist, the method including the steps of
- engaging the yarn strands at a first point downstream of the twisting means to establish a twist trap point;
- reversing the twist direction of said twisting means;
- engaging the yarn strands at second and third points spaced upstream and downstream, respectively, of said first point and downstream of said twisting means, the spacings between the first point and the second and third points being chosen to include substantially equal numbers of turns of opposite twist between said first point and said second and third points respectively;
- releasing the strands at said first point to permit the strands between said second and third points to untwist;
- joining the strands together between said second and third points to form joined nodes of twist reversal;
- and
- releasing the strands at the second and third points and permitting the strands to self-twist.
An apparatus for repetitively joining yarn strands at longitudinally spaced points in a continuous yarn production system of the type having means for forming and longitudinally moving a plurality of yarn strands and reversible twisting means for imparting false twist to each of the longitudinally moving strands in alternating length segments of S and Z twist, comprising the combination of
- first means downstream of the twisting means for gripping the yarn strands at a first point at which the twist in said strands reverses;
- second means for gripping the strands at second and third points on opposite sides of said first point relative to the direction of motion of the strands,
- said first and second means being longitudinally movable with the strands;
- control means for actuating said first and second gripping means in sequence and for causing said first means to be released after actuation of said second means;
- and
- fluid jet means for directing a jet of fluid under pressure at said strands between said second and third points to entangle the fibers of said strands and thereby join the strands together.
Dependencies are inferred from the claim text.